Track element for intermittent inductive train-control systems



March'26, 1929. c. s. BUSHNELL TRACK ELEMENT FOR INTERMITTENT INDUCTIVE TRAIN CONTROL SYSTEMS Filed Nov. 27, 1925 @w 5 1 WMM retreatedula. zerieo. i p a UNITED STATES PATENT oI- F c CHARLES s. BUSHNELL, or EocHEsTER, NEW yoitx, ASSIQ-NOR-TO GENERAL EATE- WAY SIGNAL COMPANY, or ROCHESTER, NEW YORK.

TRACK ELEMENT on INTEBMITTENT INDUCTIVE TRAIN-CONTROL SYSTEMS.

v Application filed November 27, 1925. Serial No. 71,750. Y

This invention relates to automatic train mounting thereof along the trackway and; control and more particularlyconcerns trackto protect the inductor from injury; and to way influence communicating means for an provide suitable protective means for enautomatic train control system of the 'interclosing the wires leading to the inductor mittent inductive-type. .winding. In one type of the intermittent inductive Other objects, advantages and charactertrain control system, influences are communiistic features of the invention will become apcatedfrom the trackway to a moving veparentas the description thereof progressesf .hicle by means of a change in the reluctance" In describing the invention "in detail, ref- 0 pt aniagnetic circuit in a car-carried receiverence will be made to the accompanying 65 ing device which occurs when such device drawings in which passes'in close proximity to magnetic bodies Figure 1 is a top plan view of;the inductor or'inductors located at spaced points along structure secured to the several ties ofa the trackway. In a system of this type, a railroad trackway, certain portions of the restrictive or retarding efiec-t, causing an casing being broken away to show the inte- 7 automatic brake application. or other si1it-' rior construction; able restriction, is produced when the above Figure 2 is a side view of the housed in mentioned influence is transmitted. In order duct6r, half ofthis view being in section; to control the transmission of this retarding Figure 3 is a section taken on the line 33 influence in accordance with tralfic condiof Fig. 1 and viewed in the direction of the 7 times, a coil or winding is provided on the arrows; and

inductor which acts when short circuited to Figure 4 is a section taken on the line 4-4 choke or suppress the magnetic flux thereof Fig. 1 and viewed in the direction of the through, the circuit through this' coil being arrows.

controlled by. suitable track relay or signal Referring to the drawing, the housed in- 80 controlled coritacts. ductor structure of 'the present invention" The magnetic structure or inductor is neccomprises in a. general .way a casing 1 enessarily located along the trackway in closeclosing a core structure 2 having a winding ,pizoximity to the track rails and is therefore 3 thereon. The core structure 2 together .30 exposed to the action of the elements and to with the winding 3 are identical with the 5 p the possibility of injury from' dragging core structure and winding shownand deequipment on trains. For this reason the scribed in my copending application Serial inductor'must be protected by a suitably #694,993, filed February 25, 1924, and for substantial housing which may be conventhis reason" these parts will be described in iently mounted near the track rails. .As the a brief manner "only in the present appli- 90 air gap through which the inductive impulse cation. r v acts 'must benecessarjly rather large due to The core structure2 is of general U-shape, the clearance-which must be maintained, the and is formed of laminated ma etic matemagnetic circuit of the inductor must have rial The .laminae used-in forming the core 40 a low reluctance, and all eddy current. or have their back yoke portions formed in 95\ other core losses in the inductor structure or different widths and are stacked to give the in the housing must be reduced to aminiback yoke a cruciform cross section as clear; mum. As the restrictive or stopping .im- 1 shown in Fig. 4, the end portions of/ail of ;pulse is transmitted when the inductor windthe laminae extending upwardly to form the" 5 mg is open circuited, the-lead'wires connectrectangular upstanding legs 4 of the core. loo

ed to 'this'winding must be suitablypro- In the corners, betweenthe projecting "ends. I tected against possible cross connection. of the cruciform back yoke are provided With the above andother considerations quarter round strips constructed of suitable" in mind it is proposed in accordance with insulating material, such as wood, so that so the presentinventidn to provide a'trackway the yoke together with thestrips'5 is .ofreclo J -inductor for intermittent inductive train contangular vcrdsssection having rounded cor- .I trol systems which has a magnetic circuit of ners; The laminae and the strips 5 are selow'reluctance, which is provided with a suit- 'cure'dj together atthe ends of. the back yoke v. able winding and whichlis enclosed in a subby the clamping blOCkSrfi these blocks also stantial 'li'ousing shaped to facilitate the serving as end supports for -the winding 3. v lio- The upstanding end portions or legs 4 of the present invention, the slots 26 are filled the core structure are flared apart and a by strips of insulating. material 27 which wooden block- 7 is inserted therebetween, are forced into these slots and frictionally being clamped in place by the bolts 8 passheld in place. These insulating strips 27 ing through the side plates 9. The pole prevent theeptrance of dirt, water, cinders, pieces 10 are secured to the ends of the uporother foreign matter to the interior of standing legs 4 oftheeore 2 by the bolts 11 the casing 1, and also prevent the possibility passing through the blocks 7 and the plates of an electrical circuit being established 12. t r across the slots 26 by small particles of con- 'Ihe'casing 1 is of general U-shaped longi- 1 ducting ,material which" might collect in tud-inal cross section as shown, having these slots. I s ramped or inclined ends 13 and a central Ihe plane upper surface of the casing 1 portion having a horizontal plane upper suris provided with slot 28 extending longiface therebetween. The casing, which is 1 tudinally along the center thereof and conmade of bronze, brass, or some other suitnecting theopenings and 21. This slot able non-magnetic metal,,is preferably cast serves to prevent the flow of eddy currents in asinglepiece to simplify its construction in a closed circuit through the casing around g and to provide ajsurface which will readily the pole ,pieces '10. A strip of insulating withstand and ward off blows from dragging material 29 is inserted in the slot 28, which 2O -or'projecting vehicle apparatus. Theramped strip is turned over within the casing and ends 13 of the casing 1 are suitably braced, is riveted to, the inner surface thereof by the or strengthened by the integral webs 14. and rivets 30 as clearly shown in Fig. 4.

'15 and are provided with outwardly pro- The casing 1 is 'of substantially inverted jecting integral lugs or flanges 16 having U sha'ped cross section in its central portion, holes 17 therein to receive the bolts or-lag having downwardly extending side walls 31 screws 18 whereby the casingis secured to. and end walls- 32 as shown in Figs. 2 and 4. the several ties 19 of a railroad trackway. The open lower side of the central portion The casing 1 is preferably made of such -of the casing 1v is closed by a cover portion length, and the lugs'16 are so spaced there- 33" of general U-shaped cross section, made on that the holes 17 will cooperate with the of a suitable non-magnetic metal such as ties 19 which in practiceare spaced at fixed cast aluminum. The cover 33 is provided and predetermined distances. ,The extremiwith outwardly extending flanges 34 at its ties of the ram ed ends 1B of the casin are upper" ed es these flanges bein arran ed p b ,b 7 b h preferably rounded as shown, and are formed to engage the downwardly extending walls toextend beyond and below the ties 19*s6 '31 and 32 of the casing 1 as clearly shown that there is little or no danger of the ass in Figs. 2 and 4. The cover 33 is securely ingbeing torn from place by dragging veclamped in engagement with the casing 1 hicleequipment. In'practice, the casing is y means of the bolts 11 which hold the preferably mounted outside of the track rails p le pieces 10 0 the ends Ofthe core Strucand parallel thereto. ture 4, these bolts being provided with a i 1 is provided with two aligned elongated ends 35 which pass through holes openings, 20 and 21 located at the extreme near the ends of 'the'cover 33, the lock nuts ends ofitheplane upper surface thereof and '36 being provided on the lower ends of the extending the 'entir width f the a ing; bolts '11 to clamp the cover 33 in place. The The pOle-piecesJO of the core structure 2 are bol 11 are insulated from th v r 33 by supported inthe openings 20 and 21 on the means f he insulating s g 3 inwardly projecting flanges 22 as shown in 'One end of th Cover portion is pro- Figs. 2 and and are insulated from elec- Vided, With a ecta g a p ck 1 Off-Set till trical contact with the casing 1 b th i portion38 as most clearly shown in Fig. 3.

' l tin v h rs 23 a t l rly h w This pocket 38 is provided with openings in Figs. 1- and 2. The washers 23 are ub- 39 and 40 in the opposite side surfaces therestantially rectangular in shape having large of, and a junction box 41 is clamped over openings 2f]: tlgerein to receive the upstanding one of these openings 40-.by means of the d -4 fth core t t d arg vid d machine screws 42. 'A terminal block 43 of ,with upturned nds 25 t insul t th d insulating material is secured within the of the pole pieces 10 fro mthe casing 1. junction box 41 by the machine screws 42 I As pointed-out in my cU-pending applias clearly shown in Fig. 1, this block 43 'cation referred to above,'the pole pieces 10. being provided with slots for the reception are made of a suitable magnetic material of the leads 44 of the winding 3, and with and are provided with slots 26, extending suitable term nals 45. The junction box 41 from one edge thereof toward the center to a; is provided with conduit outlets 46 at. its point where the core structure 4 engages the opposite ends, these outlets being provided pole piece, These slots 26 serve to prevent with suitable conduit connecting clamps as theflowof eddy currents in the pole pieces in shown. It should be noted that the conduit a circular path around the 'core structure. In outlets 46 are as widely separated as pos-.'

. tion box 41 is connected, is provided to peror control apparatus.

mit the junction box 41 being secured to either side of-the inductor casing 1 .as desired, this opening'39 being preferably closed when not in use by a removable cover 50 which is held in place by the screws 51.

From the description given it will be evident that an extremely simple, rugged and compact construction has been provided for mounting-and protecting the trackway inductor and its winding. Eddy current losses in the casing as a result of changes in flux through the core are prevented by the provision of the slots in the casing and the pole pieces, and similar losses in circuits through the core in series with the cover portion 38 or the casing 1 are prevented by the insulating bushings 37 and the insulating washers 23. Because of this insulation of all possible eddy current circuits, the reluetai'ice of the magnetic circuit through the core 1 is reduced to a minimum. The junction box'll provides a convenient means for connecting the leads to the winding 3 through suitable conduits with the signal This junction box may be attached on either side of the inductor casing, thus permitting the inductor to be used on either side of the track rails. As the present invention has been shown in a rather specific form and in connection with certain specific details of construction,

it should be clearly understood that certain changes, modifications, and improvements may be made without departing from the scope of the invention as defined by the appended claims.

What it is desired to secure by Letters Patent is 1. In an influence communicating device for automatic train control systems, a U- shaped core of magnetic material, a housing for said core comprising a one piece casing having inclined ends, the central port-ion of said casing being of inverted U-shaped cross section, means for supporting said core from the upper surface of said central portion, and a U-shaped cover portion supported by said core to enclose said core within said central portion.

2. In an influence communicating device for automatic train control systems, a U- shaped core of magnetic material, a housing for said core comprising a one piece metallic casing having inclined ends and a central portion, downwardly extending walls on said central portion, means for supporting saidv core from the upper surface of said central portion, and a cover secured to said central port-ion in engagement with said walls and enclosing said core.

3. In an influence communicating device for automatic train control systems, a U shaped core of magnetic material, a housing for said core comprising a one piece metallic casing having inclined ends, means permitting said casing to besecured to a support,

the central'portion of said casing being of;

inverted U-shape with downwardly extending side andend walls, openings in the upper surface of said central portion, means for supporting said core within said central portion from said openings, and a cover engaging said side and end walls and enclosing said core;

4. In an influence communicating device for automatic train control systems, a U.- shaped core of magnetic material having upstanding legs and pole pieces secured to said legs, a housing for said core comprising a one piece metallic casing having inclined ends and a central portion, said central portion being of substantially inverted U-shaped cross section openings in the upper surface of said central portion, means for securing said pole pieces in said openings, a metallic cover for said central portion secured to said core, and means for insulating said core from said casing and from said cover.

5. An influence communicating device for automatic train control systems comprising a U-shaped core of magnetic material, pole pieces secured to the extremities of said core, and a housing for said core comprislng a one piece metallic casing having inclined ends, integral means on said ends for permitting said casing to be secured to a support, extensions on said ends adapted to extend below the upper surface of said support, said casing having a central portion of substantially inverted U-shaped cross section, openings in the upper surface of said central portion, means for supporting said core in said central portion with said pole pieces in said openings and flush with the upper surface of said central portion, a winding on said core and a cover secured over the lower part of said central portion' and enclosing said core. c

6. An inductive influence communicating device for automatic train control systems comprising a; U-shaped core of magnetic material having pole pieces, a housing for said core comprising a one piece metallic casing having inclined rounded ends and a hollow central portion, openings in the upper surface of said central portion, said pole pieces being supported in said openings and said core extending within said hollow central portion, a coil on said core and a slot in Y the upper wall of said central portion between said openings.

7. An inductive influence communicating device for automatic train control systems comprising a U-shaped core of magnetic material having pole pleces, a housing for said corecomprising a one piece metallic casing having inclined rounded ends and a central portion of inverted U-shaped cross section, openings in the upper wall of said central portion, said pole pieces being supported in said openings with their upper surfaces flush with the surface of the'casing, slots in said pole pieces, a slot in the upper wall of said central portion connecting said openings, and insulating material in said slots.

8. An inductive influence communicating device for automatic train control systems comprising a U-shaped core of magnetic material having pole pieces, a housing for said core comprising a one piece metallic casing having inclined rounded ends anda hollow central portion of inverted U-shaped cross section, said central portion having a plane horizontal upper surface with aligned openings at the opposite ends thereof, a slot in said upper surface connecting said openings, means for supporting said pole pieces in said openings with said core insaid hollow central portion, means for electrically insulating said pole pieces from said casing, a lower cover for enclosing said core in said hol low portion, means attached to said core for securing said cover portion to said hollow central portion, and means for electrically insulatingsaid cover from said core. 1

9. An inductive influence communicating device for automatic train control systems comprising a U-shaped core of magnetic material having pole pieces, slots in said pole pieces filled with insulating material, a housing for said core comprising a one piece me tallic casing having aligned openings therein, a slot in said casing connecting said openings and filled with insulating material and means for supporting said polepieces in said openings with said core extending with in said casing.

10. An inductive influence communicating device for automatic train control systems comprising a U-shaped core of magnetic material, a housing for said core comprising a one piece metallic casing having inclined ends and a hollow central portion of inverted U-shaped cross section, aligned openings in said central portion, pole pieces supported in said aligned openings, a cover for completely enclosing said hollow central portion and means for securing said core to said pole pieces, said means also connecting said cover to said casing. i

11. An inductive influence communicating device for automatic train control systems comprising a U-shaped core of magnetic material, a housing for said core comprising a' one piece metallic casing having inclined ends and a hollow central portion of inverted, U-shaped cross section, said central portion being open on its lower side and having aligned openings in its upper surface, pole pieces supported in said aligned openings and insulated from said casing, a metallic cover for closing said open lower side of said central portion, and means passing through said hollow central portion for clamping said pole pieces and said cover to said casing, said core being supported within said casing by said means, said means being insulated from said cover.

12. In an inductive communicating device for automatic train control systems, a U- shaped core of laminated magnetic material, a portion of the laminae of said core being narrower than the remainder along the back yoke of said core and all of said lamina having integral upstanding ends, said laminae being stacked to form a core having a back yoke of cruciform cross section, a winding on said back yoke, a casing for said core having aligned openings therein, pole pieces supported in said openings and means for securing the upstanding ends of said core to said pole pieces whereby said core is supported within said casing.

13. In an inductive influence communicating device for automatic train control systems, a U-shaped core of laminated magnetic material, the laminae of said core having two different widths along the back yoke thereof and being stacked to provide a back yoke of cruciform cross section, all of the laminae having integral upstanding rectangular ends forming the legs of said core, a one piece hollow metallic casing having openings in the upper surface thereof, pole pieces supported in said openings and insulated from said casing, and a slot in the upper surface of said casing between said openings, said core being supported within said casing from said pole pieces.

14. An inductive influence communicating device for automatic train control systems comprising a U-shapedcorc of magnetic material having pole pieces, a one piece metallic casing for said core having inclined ends and a hollow central portion, said central portion having openings in the upper surface thereof and being open on its lower side, means for securing said core within said casing with said pole pieces in said openings, a winding on said core, a cover for said open lower side of said casing and a junction box secured to said cover.

15. An inductive influence communicating device for automatic train control systems comprising a U-shaped core of magnetic material havingpole pieces, a one piece metallic casing for said core having inclined ends and enclosing said core, a junction .box, and.

means for attaching said junction box to said cover on either side of said casing.

16. An inductive influence communicating device for automatic train control systems comprising a U-shaped core of metallic-material having upstanding legs, pole pieces secured tothe ends of said legs, the edges of said pole pieces extending laterally beyond said legs, said pole pieces having openings therein preventing the flow of current in said laterally extending edges thereof, a housing for said core comprisinga one piece 'metallic casing having inclined ends, and

openings in the upper surface of said casing to receive said pole pieces.

17. In an inductive mfluence communicating device for automatic train control systerns, a U-shaped core of laminated magnetic material having upstanding legs, each of surface thereof, pole pieces secured in said opening and means for ,positioning the core Within the casing by securing said upstand ing legs of said core to said pole pieces.

18. In an inductive influence communicat ing device. for automatic train control sys-' terms, a U-shaped core of laminated magnetic material having upstanding legs and a back yoke, a winding on 'saidback yoke, longitudinal strips of insulating material inserted between said winding and said back yoke, a hollow one piece metallic casing for said core and means' for supporting said core within said casing.

19. In an inductive influence communicating device for automatic train control systems, a U-shaped core of laminated magnetic material having upstanding legs and a back yoke a Windingon the back yoke,-an'gular longitudinal strips of insulating material in-' serted between said winding andsaid back yoke, a hollow one piece metallic casing for said core, and means for supporting said core within said casing.

20. In an inductor, a laminated core of cruciform cross section, elongated angular strips of insulating material fitted into the angles of the core section, and a winding around the core andstrips.

In testimony whereof I aifix my signature.

CHARLES S. BUSHNELL. 

